Climate Regulation by Capturing Carbon in Mangroves

Abstract

Mangroves play an important role in regulating climate by sequestering carbon within soils and to a lesser extent in forest biomass, as well as exchanging carbon dioxide with and emitting methane to the atmosphere. The rate of soil accretion averages 5.8 mm yr−1 with most measurements between 0 to 2 mm yr−1. The median is 3 mm yr−1 with one standard error of 1.0 mm yr−1. The average carbon sequestration rate is 171 g Corg m−2 yr−1 with a median of 103 g Corg m−2 yr−1. Assuming a global area of 137,760 km2, and using the median value, carbon sequestration in mangroves equates to 24 Tg Corg yr−1. Assuming a destruction rate of 1-2% yr−1, we can estimate a loss of carbon equivalent to 5 to 11% to recent estimates of global deforestation. These losses also offset 23-49% of the carbon sink in the global ocean continental margins. The range of these losses underscores the global consequences of continuing mangrove losses to the global carbon cycle.